6-methyl, 9alpha, 21-difluoro, 11 oxygenated, 17alpha hydroxy-4-pregnene-3, 20 dionesteroid compounds



6-METHYL, 9oz, ZI-DIFLUORO, 11 OXYGENATED,

17m HYDROXY-4-PREGNENE-3,20 DIONE STER- 01D COMPOUNDS Frank H. Lincoln, Jan, Kalamazoo, William P. Schneider, Kalamazoo Township, Kalamazoo County, and George B. Spero, Kalamazoo, Mich., assignors to he Upjohn Company, Kalamazoo, Mich, a corporation of Michigan No Drawing. Application March 6, 1957 Serial No. 644,200

' 4 Claims. (Cl. 260-39745) and now abandoned, and Serial No. 623,763, filed November 23, 1956.

The new compounds and the process of the present invention are illustratively represented by the following sequence of formulae:

2,867,635 Patented Jan. 6, 1959 ice CH5 CH5 (JHQF (IJHQF 0:0 1 0: '----0H 0H Hofii 1 O :1 CH3 CH3 i 0: O:

CHa VIII Ha VII Alternatively, the new product VIII can be made by the following sequence of steps: 7

CH3 CH3 CHsOAG CHrOAO =0 =0 -"OH '"OH (EH; X XI CH3 -CH5 (intone v CHzOAc C=O v i ---orr ---0H \O I HO X 011 CH9 CH3. XIII A CHa XII r ---orr CH3 1 V x 0= pochlorous' or hypobromous acid H3 VIII wherein X is a halogen of atomic number between 17 and 35, inclusive, R is an organic radical such as methyl, ethyl, phenyl, tolyl, naphthyl, or the like, with methyl preferred, and Ac is the acyl radical of an organic carboxylic acid, preferably a hydrocarbon carboxylic acid containing from one to eight carbon atoms, inclusive.

The process of the present invention represented by the sequence of Formulae I thru IX comprises: treating 6-methyl-1 118,170:,2'1-trihydroxy-4-pregnene 3,20 dione as sodium iodide in acetone solution to obtain 6-rnethyli 11,8,17u-dihydroxy-2l-iodo-4-pregnene 3,20-dione (III); treating the thus obtained 6-methyl-11;3,17a-dihydroxy- 21-iodo-4-pregnene-3,20-dione with silver-"fluoride, preferably in acetonitrile solution, to obtain 6-methyl-1 1 13,17ozdihydroxy-Z1-fiuoro-4-pregnene-3,20-dione (IV); .alternatively 6 methyl 11 3,l7a,dihydroxy-21-fluoro=4-pregnene-3,20-dione is obtained by treating the sulfonate II with potassium fluoride as shown in Example 19; dehydrating the thus obtained 6-methyl-l1 ,8,l7u-dihydroxy-21 fiuoro-4-pregnene-3,20-dione, for example, with thionyl chloride or preferably with an acid N-haloamide or N- haloimide and then with anhydrous sulfur dioxide to obtain the corresponding 6-methyl-17a-hydroxy-21-fiuoro- 4,9(11) pregnadiene-3,20-dione (V); treating the thus obtained 6-methyl-17a-hydroXy-2l-fiuoro-4,9(11) pregnadiene-3,20-dione with a hypohalous acid such as hypreferably produced in situ by adding an N-haloacylamide or N-haloacylimide 1n the presence of an acid to obtain the corresponding 6-methyl-9ot-halo-11fi,17u-dihydroxy 21 -fluoro 4'-pregnene-3,20-dione (VI); treating the thus obtained 6-methyl-, 9a,halo-I l ,8,17u-dihydroxy- 21-fluoro- 4 pregnene 3,20-,

dione with a mild base, for example, sodium or potassium acetate toobtain the corresponding 6-methyl-9 3,1l 5-oxido-17a-hydroxy-21-fluoro-4-pregnene-3,20-dione (VII) treating the thus obtained oxido compound VII with hydrogen fluoride to obtain 6-methyl-9a,2l-difiuoro-l15,

4 17a-dihydroxy-4-pregnene-3,20-dione (VIII), and if desired oxidizing the thus obtained 6-methyl-9a,21-difluoro- 1l5,17a-dihydroxy-4-pregnene-3,20-dione with chromic anhydride or a dichromate or other oxidizing agents to obtain 6-methyl-9a,2l-di-fluoro-l7a-hydroxy-4-pregnene- 3,11,20-trione (IX).-

In thealternative process the steps of fluorination are reversed so that first the 9a-fluoro group is introduced into the 6-methylhydrocortisone ester and thereupon the 21-hydroxyl group is replaced with fluorine. The process comprises the following steps: dehydrating a 6-methylhydrocortisone 2l-acylate with thionyl chloride, or preferably an acid N-haloamide or N-haloimide and then with anhydrous sulfur dioxide to obtain 6-methyl-l7u, 21-dihydroxy-4,9( 1 1 -pregnadiene-3,2 0-dione 2l-acylate (XI); treating the thus produced6-methyl-17a,21-dihydroxy-4,9( l1)-pregnadiene-3,20-dione Zl-acylate with a hypohalous acidsuch as hypochlorous or hypobromous acid, preferably by producing the hypohalous acid in situ, for example, in a mixture of N-haloacylamide or N- haloacylimide 'in the presence of acid, to obtain the corresponding 6 methyl-9d halo-11;8,17a,21-trihydroxy- 4-pregnene-3,20-dione 21-acylate (XII). Treating the thus produced 6-n1ethyl-9a-hal0-11fi,17rx,2l-t1ihydroxy 4-pregnene-3,20,-dione 21-acylate with a base such as anhydrous potassium acetate or anhydrous sodium acetate yields the corresponding epoxy compound, 6-methyl- 918,1lfi-oxido-17a,21-dihydroxy-4-pregnene-3,20-dione 21 acylate (XIII); treating the thus obtained 6-methyl- 95,1 1 fi-oxido-17oi,2l-dihydroXy-4-pregnene-3 ,20-dione 21- acylate with hydrogen fluoride yields thef'corresponding 6-methyl-9a-fluoro 11,6,17oz,2 1 trihydroxy 4-pregnene-3,20-dione 21-acylate (XIV); hydrolyzing this ester in conventional manner with a base preferably in a nitrogen atmosphere yields the triol, 6- me'thyl-9a-fluorohydrocortisone (XV). Treating the thus'obtained 6-methyl- 9a-fluorohydrocortisone with an organic sulfonyl halide, such as methanesulfonyl chloride, toluenesulfonyl chloride, toluenesulfonyl bromide, benzenes'ulfonyl chloride, naphthylsulfonyl chloride, or the like, yields the corresponding 6-methyl-9a-fluoroh'ydrocortisone 2l-organic sulfonate (XVI); treating the thus obtained sulfonate of 6-rnethyl-9a-fluorohydrocortisone with sodium iodide in acetone solution yields 6-methyl-9a-fiuoro-11,8,17u-dihydroxy-Zl-iodo-4-pregnene-3,ZO-dione (XVII); and treating the thus obtained 21-iodo compound (XVII) with excess of silver fluoride, preferably in acetonitrile solution yields 6-methyl-9a,2l-difluoro-11,8,17a-dihydroxy-4- pregnene-3,20-dione (VIII). Alternatively, treatingsulfonate XVI with potassium fluoride as shown in Example 19 produces 6-methyl-9a,21-difluoro1l 3,l7a-dihydroxy- V 4-pregnene-3,20-dione (VH1).

It is an object of the instant invention to provide novel 6-methyl-9a,2l-difluoro-l1,6,17adihydroxy 4-pregnene- 3,20-dione and the keto analogue thereof, 6-methyl-9a, 2l-difluoro-l7a-hydroXy-4-pregnene-3,11,20-trione. It is another object of the instant invention to provide methods for the production of 6-methyl-9a,21-difiuoro-11,8,17a-di- V hydroXy-4-pregnene-3,20-dioner and 6-methyl-9u,21-difluoro-l7a-hydroxy-4-pregnene-3,11,20-trione. Other objects of this invention will be apparent to those skilled in the art to which this invention pertains.

The novel compounds of the present invention, 6- methyl-9a,2l-difluoro-l113,170: dihydroxy 4 pregnenebut have distinct diuretic qualities, The novel synthetic corticosteroid hormones, 6a-methyl-9u,2l-difluoro-l1,8, 17a-dihydroXy-4-pregnene-3,ZO-dione and 6a-methyl-9oa,

sess also strong anti-inflammatory activity and are thus useful in the management of arthritis, especially in cases L Where in addition to chronic congestive heart failure, neophrotic syndromes and other circulatory symptoms are present. The compounds may be given as oral compositions and tablets, illustratively, using either polyethylene glycol 4000 or 6000 as a carrier, or lactose and/ or sucrose as diluent. Especially useful is the novel 6a-methyl-9a,21- difluoro 115,17ot dihydroxy 4 pregnene-3,20-dione which can also be used in topical applications such as ointments, lotions, jellies, creams, suppositories, bougies, aqueous suspension etc. Examples of advantageous topical preparations are given below. While the examples below are to the 6a-methyl-9a,21- difluoro-l1B,171x-dihydroxy-4-pregnene-3 ,20-dione, equivalent amounts of 6a-rnethyl-9a,21-difluoro-l7a-hydroxy- 4-pregnene-3,l1,20-trione, the 6fi-epimers and other 6- lower-alkyl and 6-phenyl homologues of the compounds of this invention are substitutable therein.

A dermatological and ophthalmic ointment has the following composition:

Pounds Wool fat, U. S. P 100 Mineral oil, U. S. P 125 6ot-methyl-9a,2l-difluoro-l l {3,170c-dil1Yd1'OXY-4 pregnene-3,20-dione (micronized) White petrolatum, U. S. P 500 Incorporation of an antibiotic in the ointment, especially neomycin sulfate, has therapeutic advantages, each active ingredient potentiating and supplementing the useful properties of the other. Such an ointment is as 6u-methyl-9a,2l-difluoro-l1/3,17a-dihydroxy-4 pregnene-3,20-dione (micronized) White petrolatum, U. S. P v 500 In place of, or in addition to, neomycin sulfate, other antibiotics such as bacitracin, circulin, polymyxin B sulfate, grarnicidin, streptomycin sulfate, dihydrostreptomycin sulfate, oxytetracycline, chlorotetracycline, tetracycline, chloramphenicol and the sulfonamides can be used in conjunction with the steroids of the present invention for preparations such as the above ointments.

In carrying out the process of the instant invention the selected 6-alkylor 6-arylhydroc0rtisonc (6-alkylor 6- aryl-l1,8,17,2l-trihydroxy-4-pregnene-3,20-dione) (I) is treated with an acid halide of a sulfonic acid such as methanesulfonic acid, ethanesulfonic acid, propanesul fonic acid, benzenesulfo-nic acid, p-toluenesulfonic acid, aor fl-naphthanesulfonic acid, or the like with methanesulfonic acid halides especially methanesulfonyl chloride preferred. In the preferred embodiment of the instant invention the steroid is reacted with the alkylor varylsulfonyl halide in solution such as in a solvent, for example, pyridine, benzene, toluene, or the like, at a temperature between minus ten and plus thirty degrees centigrade providing that at the lower temperature the solvent has not solidified. Pyridine is the preferred solvent and a temperature between minus ten and plus ten degrees centigrade is preferred. The time of reaction is usually between thirty minutes and six or eight hours after which the product, 6-alkylor 6-aryl-l1B,l'7et,21-trihydroxy-4- pregnene-3,20-dione 21-alkylor arylsulfonate is removed in conventional manner, for example, by evaporating the solvent until a dry residue is precipitated or by extracting the material from an aqueous solution. For extraction, solvents such as methylene chloride, chloroform, carbon tetrachloride, benzene, ether, toluene, or the like can be used. Removing the extraction solvent by distillation leaves the crude 6-alkylor 6-aryl- 11,8,- 17a,21-trihydroxy-4-pregnene-3,20 -dione 21-alkylor arylsulfonate (II).

For the purpose of producing the final product, it is fluoride solution rather than solid silver fluoride.

d unnecessary to purify the thus obtained 2l-alkyl-or 21 arylsulfonate and the crude steroid sulfonate ester can be used for the production of 6-a1kylor 6-aryl-11fi,17otclihydroxy-2l-iodo-4-pregnene-3,20-dione.

The Zi-iodo compound is prepared by reacting the Zl-allrylor arylsulfonate of 6-alkyl or 6-aryl-11,B,l7a,- 21-trihydroxy-4-pregnene-3,20-dione with sodium or potassium iodide in a dialkyl ketone solution such as acetone solution. A molar excess of sodium iodide (three to twenty moles of sodium iodide per mole of steroid) is generally preferred for this reaction; and the reaction mixture containing 6-alkylor 6-aryl-1lB,17a,2l-trihydroxy-4pregnene-3,20-dione 21-alkylor arylsulfonate and the sodium iodide in acetone is heated to reflux for a period of three or four minutes to half an hour. ,The thus produced 6-alkylor 6-aryl-11p,17ot-dihydroxy-21- iodoi-pregnene-3,ZO-dione is isolated by evaporating the solvent. For the subsequent reaction it is unnecessary to carefully purify the thus obtained 6-alkylor 6-aryl- 1 1B, l7ot-dihydroxy-2l-iodo-4-pregnene-3,20-dione (III).

In order to obtain 6-methyl-11fi,17a-dihydroxy-21- fluoro-4-pregnene-3,20-dione, the crude 6-alkylor 6- aryl-11,B,17 a-dihydroxy-21-iodo-4-pregnene 3,20 dione, dissolved in a suitable solvent such as acetonitrile, hexanes, heptanes, benzene, tertiary butyl alcohol, or the like with acetonitrile preferred, is reacted with silver fluoride. The reaction is usually carried out under exclusion of light and-with stirring. The preferred form of silver fluoride used is a fifty percent aqueous silver The reaction is generally carried out between forty to sixty degrees centigrade; however, lower or higher temperatures between ten and about 75 degrees centigrade are operative. Since the silver iodide produced in the reaction forms a molecular compound with silver fluoride, two moles of silver fluoride must be used per mole of steroid as the minimum amount necessary for theoretical recovery. However, it is preferred to use an even greater amount, between ten to fiftypercent over and above the calculated amount, in order to obtain higher yields. The silver fluoride is generally added in portions over a period of time, the reaction time ranging usually from one half to six hours. In order to isolate the product, the solvent is evaporated and the crude product 6-alkylor 6-aryl- 11p,l7a-dinydroxy-21-iluoro-4-pregnene-3,ZU-dione (1V) extracted with a suitable solvent such as chloroform, methylene chloride, carbon tetrachloride, benzene, or the like. Purification is made by conventional procedures such as additional extraction to eliminate impurities, recrystallization or chromatography, as deemed necessary.

' droxy-Z1-fluoro-4-pregnene-3,20-dione is dehydrated to the corresponding o-ailgylor 6-aryl-21-fluoro-lh-hydroxy-4,9(1l)-pregnadiene-3,20-dione by methods known in the art, for example, by dehydrating agents such as phosphorus oxychloride, hydrochloric acid or sulfuric acid and acetic acid, thionyl chloride, by pyrolysis as shown by U. S. Patents 2,640,838 and 2,640,839, and the like. In the preferred embodiment of the presentinvention the dehydration is eiiected by reacting the 11 3- hydroxy compound with an acid N-haloamide or N- haloimide in an organic base and treating the thus produced intermediate ll-hypohalite with dry sulfur dioxide in an organic base. As reagents for the production of an ll-hypohalite, the acid N-haloamide or N- haloimide are used wherein the halogen has anatomic number from 17 to 53,-inclusive, preferably, chlorine or bromine. Examples of such compounds are N-chloroacetamide, N-bromoacetamide, N-chlorosuccinimide, N- bromosuccinimide, N-iodosuccinimide, 3-bromo-5,5- dimethyl hydantoin. Ordinarily an amount in excess of a molar equivalent, calculated on the starting lip-hydroxy steroid, is employed. The base employed in the production, of 'the l'l-hypohalite are. tertiary amines wherein the amino nitrogen is a member of an aromatic ring, for example, the pyridines, that is, pyridine, alkylpyridines, piccoline, lutidine, collidine, conyrine, parvuline, or the like, or lower fatty amides such as formamide, methylformarnide and dimethylformamide. The base is preferably employed in a large molar excess, calculated on the starting llfi-hydroxy steroid, for example, ten molar equivalents, and is preferably the sole reaction solvent. The reaction to produce an ll-hypohalite is generally conducted under anhydrous conditions preferably containing less than 0.1 molar equivalent of water calculated per mole of steroid. Large proportions of water decrease the yield. The temperature of the reaction is between minus forty and 'plus seventy degrees 'centigrade, the lower limitbeing determined by the solubility of the reaction and by the character of the solvents, and the upper limit being determined by the amount of side reaction which normally accompanies the reaction involving any halo compounds at higher temperatures. thirty degrees centigrade) is preferred for convenience and because of the consistently high'yields of the desired product which are'obtained at this temperature. A reaction period between five minutes to three hours is unually employed, at higher temperaturesabove thirty degrees centigrade-short reaction tines are sufl'icient to produce completeness of the reaction.

The thus produced 6-alkylor 6-aryl-11fi,l7a-dihy- 'droxy-21-luoro-4-pregnene-3,ZO-dione llfl-hypohalite is then treated with anhydrous sulfur dioxide in the presence of an organic base as described hereinbefore. The anhydrous sulfur dioxide can be in the form of gaseous or liquid sulfur dioxide or in the form of a material which in situ produces sulfur dioxide, for example, alkalimetal hyposulfite. The reaction temperature ranges substan tially within minus forty and plus seventy degrees centigrade and is preferably room temperature (about twenty to thirty degrees centigrade). The thus obtained product, 6-alkylor 6-aryl l7ct hydroxy-2l-fluoro-4,9( 11)-pregnadiene-3,20- dione, is isolated from the reaction mixture by conventional means such as extraction after the reaction mixture has been poured into excess of water. Organic water-immiscible solvents such as ether, chloroform, methylene chloride, carbon tetrachloride, ethyl acetate, benzene, hexanes, or the like, are used for the extraction. The thus obtained extracts are conveniently washed, dried and thereupon evaporated to give the crude nadiene-3,20 -dione (V) which is purified by conventional means such as recrystallization or chromatography, as deemed necessary. 7 V i r The thus produced 6-alkylor6-arylfl7a-hydroxy-2lfluoro-4,9(ll)-pregnadiene-3,20-dione is converted to 6 alkylor 6-aryl-9bt-halo 11,8,17 t-dihydroxy-2l-fluoro-4- pregnene-3,20-dione by adding ahypohalous acid such as hypochlorous or hypobromous acid. The hypohalous acid is'usuallyadded by reacting an N-haloacidamideor an N-haloacidimide with an acid .to produce the hypohalous acid in situ. In the preferred embodiment of the invention,'the steroid, a 6-alkylor 6-aryl-17a-hydroxy- 21-fiuoro-4,9(ll)-pregnadiene-3,20:dione is dissolved in an orgahicsolvent such as methylene chloride, tertiary butyl alcohol, dioxane, tertiary amyl alcohol, or the like, and rea'cted'at room temperature with the hypobromous or hypochlorous acid releasing agent in the presence of an acid. Such hypohalous acid releasing agent includes the l I-bron1oacetamide, the N-chloracetamide, the N-bromosuccinimide, or the like, in the presence of water and an acid such as perchloric acid, e

dilute sulfuric acid, or the like The reaction is usually carried out at room temperature, between fifteen to thirty degrees centigrade; however, lower or higher temperatures. are operative for the process. The hypohalous acid releasing agent is generally used in one molar or Ordinarily, 'room temperature (twenty to assists slightly increased, for example, 25 percent increased amounts compared to mole of steroid. ,A' large excess of the hypohalous acid releasing agent, while operative, is undesirable. since the excess of hypohalous'acid has a tendency. toreacton other positions of the molecule. Thereaction period is rather short and may vary between about four to 'five minutes to one hour. At the end of the reaction time excess of hypohalous acid is destroyed by the addition of sodium vsulfite or other sulfites or .hydrosulfites. The thus produced product, a 6-alkylor 6-aryl-9u-halo-11,8,17a-dihydroxy-21-fiuoro- 4-pregnene-3,20-dione (VI), wherein the halogen atom is of atomic weight between 33 and (atomic num: ber 17 to 35), is isolated from the reaction mixture by adding excess of water. and extracting the compound with organic solvents or. by recovering the precipitated compounds throughfiltration. Thecrude product thus obtained may be recrystallized from organicssolvents, such as acetone, Skellysolve B hexane hydrocarbons or the like to give pure 6-alkylor 6-aryl-9u-halo-11fi,17adihydroxy-Zl-fluoro-4-pregnene 3,20--dione.

Oxidizing the 6-alkylor 6-aryl-9a-halo-11;8,17u-dihydroxy-21-fiuoro-4-pregnene-3,ZO-dione with chromic acid produces the corresponding pharmaceutically active 6- alkylor 6-aryl-9ot-halo-l7a-hydroxy-2l-fluoro-4-pregnene-3,11,20-t'rione. I

In order to obtain the 9c4-fl1l0f0 compounds, the 9,8,

llB-epoxy intermediates of the before-mentioned com-' pounds, 6 alkylor 6 aryl 95,115 oxido 17a hydroxy-Zl-fluoro-4-pregnene-3,ZO-dione are prepared; in carrying out this reaction a -alkylor 6-aryl-9a-halo- 115,l7a-dihydroxy-2lrfiuoro-4-pregnene 3,20 dione is heated in solution with a mild base, and preferably in the absence of water to avoid hydrolysis of the ester groups.

The cases useful for the cyclizati on include anhydrous potassium acetate, sodium bicarbonate, sodium acetate, or the like, with potassium acetate. preferred. Solvents such as methanol, ethanol, acetone, tertiary butyl alcohol, or the like, can be used. The reaction time is between one half hour and 24 hours; generally a periodbetween three and twelve hours is sufiicient. The thus obtained o-alkylor 6 aryl 9,8,1lfl-oxido-l7ct-hydroxy-2l-fluoro- 4-pregnene-3,20-dione. is isolated. from the reaction mixture by diluting the reaction mixture with excess water and filtering .the product'when crystalline, or by extracting with methylene chloride or other Water-immiscible solvents such as ether, Skellysolve B hexanes, pentanes, benzene, ethyl acetate, chloroform, carbon tetrachloride, or the like. Evaporation of the solvent of the extracts produces the 6-alkylor 6-aryl-9,B,l lB-oxidodh-hydroxy- 21-fiuoro-4-pregnene-3,20-dione (VII). s

.The thus obtained 6-alkylor 6-aryl-9fl,11,B-oxido-l7ahydroxy-Zl-fiuoro-4-pregnene-3,20-dione is thereupon reacted with hydrofluoric acid in solution. As solvents for this reaction methylene chloride, tetrahydrofuran, ethylene dichloride, chloroform, carbon tetrachloride, and mixtures thereof or the like are useful, with methylene chloride and tetrahydrofuran preferred. With methylene chloride at room temperature, aqueous 48 percent hydrofluoric acid is generally used, while with tetrahydrofuran at low temperatures vliquid hydrogen fluoride is used. The reaction is carried out preferably with stirring at room temperature (twenty to thirty degrees centigrade) when methylene chloride is used as solvent and at low temperatures, zero to minus eighty degrees centigrade when tetrahydr ofuran is used in the presence of chlorinatedhydrocarbons. The period of reaction is from one to 24 hours with a period from one to twelve hours usually sufiicient. After the reaction is terminated, the mixtureis poured into water and neutralized with a dilute base such as sodium bicarbonate, potassium bicarbonate, or the, like. Excess of strong bases can also be used. The reaction mixture is then extracted with a water-immiscible solvent such as methylenechloride, the organic layer is separated from the water mixture, washed with water, dried and evaporated to give the crude 6-a1kylor 6-aryl-9a,21-difluoro 1118,17oc dihydroxy 4 pregnene 3,20-dione (VIII). The thus obtained crude compound can be purified through recrystallization o-r chromatography.

Oxidation of 6 alkylor 6 aryl 9a,21-difluoro-11fi, 17a dihydroxy 4 pregnene 3,20 dione in conventional manner, for example, with chromic anhydride or an alkali chromate, in solution such as in acetic acid, at temperatures between zero and forty degrees, provides the corresponding 6-alkylor 6-aryl-9a,21-difiuoro-17othydroxy-4-pregnene-3,11,20-trione.

In the alternative procedure shown as Steps X to XVII to Compound VIII, the reactions involved are the same as those described before in the steps from Compound I to VIII, except that the introduction of the 9oc-flll010 atom is made first, before the introduction of the 2l-fluoro atom. As starting material in this second procedure instead of the 6-methylhydrocortisone, an ester thereof is used such as an acetate, propionate, butyrate, pentanoate, hexanoate, benzoate, phenylacetate, or the like, of 6-methylhydrocortisone. These esters (Formula X), prepared by the usual methods of esterification such as reacting 6-methylhydrocortisone with an acid chloride, an acid bromide or an acid anhydrlde of a hydrocarbon carboxylic acid in pyridine, are dehydrated in the same manner as shown for compound I to give G-methyl-17a-hydroxy-2l-acyloxy-4, 9(11)-pregnadiene-3,20-dione (IX). This compound (X1) is submitted to the same steps as shown in the sequence V through VIII before, to give 6-methyl-9tx-fluoro- 11B,170c,2l trihydroxy 4 pregnene 3,20 dione 21- acylate (XIV) which is submitted to hydrolysis in known manner, that is with a base preferably in a nitrogen atmosphere to give the free trio], 6-methyl-9a-fiuoro-11fi, 1704,21 trihydroxy 4 pregnene 3,20 dione (XV).

Compound XV, 6 methyl 90c fluoro 1lfl,17a,21- trihydroxy-4-pregnene-3,20-dione, is then subjected to the same treatment as Compound I in the sequence I-IV, i. e., esterification with an arylor alkylsulfonate to give XVI, treating the thus obtained 21-arylor alkylsulfonate of 6 methyl 90c fluoro 11fi,17ot,21 trihydroxy 4- pregnene-3,20-dione (XVI) with sodium iodide in acetone solution to give XVII and thereupon the thus-obtained 21- iodo compound XVII with silver fluoride to give the prod-.

uct of the first procedure, i. e., 6-methyl-9a,21-difluoro- 115,170: dihydroxy 4 pregnene 3,20 dione (VIII). Alternatively, as shown in Example 19, compound VIII can be obtained by treating the sulfonate XVI with potassium fluoride.

The following examples are illustrative for the processes and products of the present invention, but are not to be construed as limiting.

EXAMPLE 1 6a methyl 11B,17a,21 trihydroxy 4 pregnene-3,20-

dione 21 mezhan'esulfonate (6 methylhydrocortisone ZJ-methanesulfonate) A solution was prepared containing one gram (2.65 millimoles) of 6ot-methylhydr'ocortisone in seven milliliters of pyridine. This solution was cooled to zero degrees centigrade and treated with 0.3 milliliter of methanea EXAMPLE 2 I 6a-methyl-11,3,17ot-dihydroxy-21-i0do-4-pregnene- 3,20-dione The crude 6a-methyl-llfi,l7a,2l-trihydroxy-4-pregnene-3,20-dione 21-methanesulfonate of Example 1 was dissolved in fifteen milliliters of acetone and treated with a solution of one gram of sodium iodide in ten milliliters of acetone. The mixture was heated under reflux with stirring for a period of fifteen minutes, the heat then reduced and the mixture concentrated to one-third volume at reduced pressure. Ice and water were added and the precipitated product collected on a filter, washed with water and dried to yield 1.1 grams of 6a-methyl-1 15,17otdihydroXy-21-iodo-4-pregnene-3,20-dione of melting point to degrees centigrade with decomposition.

Analysis.--Calcd. for C H O I: I, 26.09. Found: 1, 25.05.

EXAMPLE 3 6a-methyl-11fi,1 7|x-dihydr0xy-21-flu0r0-4-pregnene- 3,20-dione A solution of one gram of 6ot-methyl-11 8,17a-dihydroxy-2l-iodo-4-pregnene-3,20-dione in milliliters of acetonitrile (practical grade) was prepared by heating to the boiling point. After cooling to forty degrees centigrade, the solution was protected from light and 0.8 milliliter of fifty percent aqueous solution of silver fluoride was added under stirring. Stirring was continued for one hour at about forty degrees centigrade, then 0.7 milliliter of silver fluoride solution was added and after another hour of stirring another 0.7 milliliter portion of aqueous silver fluoride solution was added. Heating and stirring was then continued for a period of two hours. The brown mixture was thereupon filtered through a bed of Celite diatomaceous earth and-the filtrate evaporated at reduced pressure from a bath at a temperature of fifty degrees centigrade. The brown residue was thoroughly extracted with two one-hundred-milliliter portions of warm methylene chloride, the combined extracts washed with water, dried over anhydrous sodium sulfate and concentrated to approximately 100-mi1liliter volumes and chromatographed over fifty grams of Florisil synthetic magnesium silicate. Fractions of 200 milliliters were taken as follows:

TABLE I Fractions Solvent 1-9 Hexane-acetone, 90:10. 10-12. Hexane-acetone, 85:15. 13 Acetone, 100 percent.

Hydroxy 3440 20-keto 1724 3-keto 1645 A -double bond 1 1608 EXAMPLE 4 6 ot-m ethyl-1 7u-hydr0xy-21-flu0ro-4-pregnene- 3,11,20-tri0ne A mixture was prepared containing 0.5 gram of 60amethyl 115,17 dihydroxy 21 fluoro 4 pregnene 3,20-dione, 0.15 gram of chromic acid, ten milliliters of glacial acetic acid and one-half milliliter of water. This mixture was stirred and thereupon maintained for eight hours at room temperature. Thereafter the mixture was poured into fiftymilliliters of ice water, neutralized by the addition of dilute sodium hydroxide and the thus obtained precipitate collected on a filter and recrystallized three times from ethyl acetate and Skellysolve B hexanes to give 6a-rnethyl-17a-hydroxy-21-fiuoro-4-pregnene-3,1l, -trione.

In the same manner shown in Example 1, treating other 6a-alkylhydrocortisones with the chlorides'or bromides of toluenesulfonic acid, methanesulfonic acid and other organic sulfonic acids, gives the corresponding 21- toluene-sulfonate or, respectively, the 21-methanesulfonate, or the like, of the corresponding 6a-alkylhydrocortisones wherein the alkyl group may be methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, hexyl, or an aryl such as phenyl, or the like. Treating the thus' obtained 21-toluenesulfonate, 2lmethanesulfonate or other 2l.-alkylor 21-arylsulfonates of 6a-alkylhydrocortisoiae with sodium or potassium iodide in acetone at elevated temperature, usually reflux temperature, yields the corresponding 2l-iodo compound such as, for example, 6tz-ethyl-1118,17a-dihydroxy-21-iodo- 4-pregnene-3,20-dione, fiu-propyl-l1[3,17a-dihydroxy-21- iodo-4-pregnene-3 ,20-dione, 6a-isopropyl-11/3,1 7or-dll1Y- droxy-21-iodo-4-pregnene-3,20-dione, 6oc-bt1tyl1l,B,17ccdihydroxy-Zl-iodo-4-pregnene-3,20-dione, 6oc-iSObUIYl-1 1 8, 17a-dihydroxy-21-iodo-4-pregnene-3,20-dione, V oar-pentyl- 11B,17a-dihydroxy-21-iodo-4-pregnene-3,20-dione, 6a-hexyl-l1,8,17a-dihydroXy-21-iodo-4-pregnene-3,20-dione, 6a-

phenyl 11 3,17; dihydroxy 21 iodo 4 3,20-dione, and the like.

Treating as shown in Example 3 at reflux temperature the thus prepared 21-iodo compounds in acetonitrile with aqueous silver fluoride yields the corresponding 21-fiuoro compound such as: 6uethyl-l 1fi,17a-dihydroxy-2l-fiuoro- 4-pregnene-3,20-dione, 6a-propyl-1 15,17a-dihydroxy-21- fluoro-4-pregnene-3,20-dione, 6a-isopropyl-l 1,8,17oc-dihY- droxy-21-fluoro-4-pregnene-3,20-dione, 6u-butyl-11B,17a dihydroxy-21-fiuoro-4-pregnene-3,20-dione, 6a-isobutyl- 1118,17a-dihydroxy-21-fiuoro-4-pregnene-3,20-dione, 6a-

pregnene pentyl 11,63,171: dihydroxy 21 fiuoro 4 pregnene 1 3,20-dione, 6a-hexyl-1 15,17a-dihydroxy-21-fluoro-4-pregnene-3,20-dione, 6wphenyl-1113,17a-dihydroxy-21-fluoro 4-pregnene-3,20-dione, and the like. V 7

Instead of the 6a-methylhydrocortisone the 6 3-epimers 1 can be used in the above examples and if the conditions are kept near neutral, the 6,6-epimers, such as 6 8-methyl- 1 1A17a-dihydroxy-21-fluoro-4-pregnene-3,ZO-dione can be isolated from the reaction mixture. The thus obtained 6fi-epimers yield the 6a-epirners by treatment with acid or base in an organic solvent, e. g., ethanol'at .room temperature.

" r EXAMPLE 5 6a methyl 17oz hydroxy 21 fluoro 4,9(11)- pregnadiene-iZO-dione A mixture of one gram of 6ot-methyl-l1fi,17a-dihy droxy-21-fluoro-4-pregnene-3,20-dione, 650 milligrams of N-bromoacetamide and six milliliters of pyridine were stirred in the dark for a period of thirty minutes. The mixture was cooled in an ice-water bath and a stream of sulfur dioxide was directed onto the surface of the stirred mixture until a negative potassium iodide-starchtest was obtained. Fifty milliliters of water was then added to the mixture and the mixture was maintained at about .five degrees centigrade for thirty minutes. The precipitated white solid was filtered, washed with water and dried under vacuum. After crystallization from acetone there was obtained about 0.7 gram of 6a-methyl-17a-hydroxy- 21-fiuoro-4,9 1 1 )-pregnadiene-3,20-dione.

EXAMPLE 6 bromo 115,170; dihydroxy 21 -flu0r0= 4-'pregnene-3,20-di0ne solution was prepared containing 0.5 gram of 6amethyl 17d hydroxy 21 fluoro-4,9(11)-pregnadiene- 6oz methyl 9oz a 1 2 3,20-dione in twenty milliliters of methylene chloride and thereto was added a-solution of one milliliter of 71 per- 'cent perchloric acid in ten milliliters of water and 200 milligrams of N-bromoacetamide' in fifty milliliters of V Skellysolve B hexane hydrocarbons to give 6oq-methyl-9ocbromo 1l;9,l7a dihydroxy 21-fluoro-4-pregnene3 ,20- dione. V 7

EXAMPLE 7 V 6a methyl- 9(11) oxido 17a hydroxy 21 fluoro- 4-pregnene-3,20-dione A mixture of 0.45 gram of 6a-methy1-9a-bromo-115, 17a: dihydroxy 21 fluoro 4 pregnene 3,20 dione, 0.45 gram of anhydrous potassium acetate and twenty milliliters of acetone was heated at its refluxing temperature for a period of five hours. The mixture was then cooled and poured into water and extracted with methylene chloride. The methylene chloride extract was dried and poured over a column of 25 grams of Florisil synthetic magnesium silicate. The column was developed with Skellysolve B hexane hydrocarbons containing increasing portions of acetone. The Skellysolve B plus ten percent acetone eluate contained 6a methyl 9(11) oxide-17ahydroxy 21 fluoro 4 pregnene 3,20 dione.

EXAMPLE 8 A solution of one gram of 6a-methyl-9(11)-oxido-17a hydroxy-21-fluoro-4-pregnene-3,20-dione was dissolved in fifty milliliters of methylene chloride and thereto was added five milliliters of 48 percent hydrofluoric acidand 0.5 milliliter of 71 percent perchloric acid; The mixture was stirred vigorously for six hours and then poured into an excess of cold aqueous five percent sodium bicarbonate solution. The methylene chloride layer was separated, dried with anhydrous sodium-sulfate, and then poured over a column of 100 grams of Florisil synthetic mag-. nesium silicate. The column was developed with Skelly solve B hexanes and acetone, the fractions containing ten percent acetone were recrystallized from acetone and Skellysolve B hexanes to give pure 6a-rnethyl-9a,21-dir fluoro-l1,8,17ot-dihydroxy-4-pregnene-3,20-dione of melting point 210 to 212 degrees centigrade with decomposition and rotation [al plus 89 degrees in acetone.

Analysis.-Calcd. for C H O F F, 9.58. Found:

EXAMPLE 9 60c -'methyl 904,21 difiuoro 17cc hydroxy 4-pregnene- 3,11,20-trione i Oxidizing in the manner given in Example 4, Got-methyl- 90;,21 difiuoro 11fl,17a dihydroxy 4 pregnene-3,20-

dhme with chromic anhydride in acetic acid solution produces 6oz methyl 906,21 difiuoro 17a hydroxy 4- pregnene-3,11,20-trione.

In a manner similar to Example 9, oxidizing with chromic anhydride in acetic acid solution, other 60:- alkyl-9a,21-difluoro-11 8,17a-dihydroxy-4-pregnene 3,20- dione results in the corresponding 6a-alkyl-9a,21-difiuorol7a-hydroxy-4-pregnene-3,11,20-triones wherein the alkyl group is ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, hexyl, or an aryl, such as phenyl, or the like.

EXAMPLE 10 To a solution of 8.5 grams of 6a-methyl-1lfl,17a,21- trihydroxy-4-pregnene-3,20-dione 2l-acetate (6a-methylhydrocortisone 21-acetate) in 42.5 milliliters of pyridine was added 5.63 grams of N-bromoacetamide. After standing at room temperature for a period of fifteen minutes, the reaction solution was cooled to five to ten degrees centigrade and, with shaking, sulfur dioxide gas was pmsed over the surface until the solution gave no color with acidified starch-iodine paper. During the addition of sulfur dioxide gas, the reaction became warm. The temperature was kept under thirty degrees centigrade by external cooling and by varying the rate of sulfur dioxide addition. Thereafter to the reaction mixture 400 milliliters of ice water was added and the resulting precipitate collected by filtration. This material was recrystallized from acetone-Skellysolve E hexanes to give 5.78 grams of 6u-methyl-17a,21-dihydroxy-4,9(11)-pregnadiene-3,20- dione 21-acetate of melting point 165 to 169 degrees centigrade. The mother liquors were evaporated to a partly crystalline residue which weighed 182 grams. This material was dissolved in methylene chloride and chromatographed on 75 grams of Florisil. The column was eluted with 2000 milliliters of eight percent acetone-92% Skellysolve B and 1000 milliliters of fifteen percent acetone- 85% Skellysolve B. The eluant was collected in 200- milliliter fractions. Fractions 3 to 7, were combined, evaporated, and the residue recrystallized fromacetone- Skellysolve B hexanes to yield 0.88 gram of Get-methyl- 17d,21-dlhydTOXY-4,9( l 1)-pregnadiene-3,20-dione 21-acetate of melting points 169-172 degrees centigrade. The combined yield therefore was 6.66 grams of 82.4 percent. An analytical sample obtained by crystallization from acetone-Skellysolve B hexanes gave, 6a-methyl-l7a, 21-dihydroxy-4,9( 1 1)-pregnadiene-3 ,20-dione 21-acetate of melting point 175-176 degrees centigrade and rotation [0611) plus 91 degrees in chloroform.

Analysis.-Calcd. for C H O Found: C, 71.75; H, 7.71.

EXAMPLE l1 6et-methyl-9oc-br0m0-11B,] 7a,21 trihydroxyl-pregnene- 3,20-a'i0ne 21 acetate (dca-methyl-9a-br0mohydroc0rtisane 21 -acetate) To a solution of 5.68 grams of 6a-methyl-l7a,2l-dihydroxy-4,9(11)-pregnadiene-3,20-dione 21-acetate in 100 milliliters of methylene chloride and 250 milliliters of tertiary butyl alcohol was added a solution of fourteen milliliters of 72 percent perchloric acid in 100 milliliters of water followed by a solution of 2.34 grams of N- bromoacetamide in' sixtymilliliters of tertiary butyl alcohol. After stirring the reaction mixture for fifteen minutes, a solution of milliliters of water was added and the reaction mixture was concentrated to a volume of about 500 milliliters under reduced pressure at about fifty degrees centigrade. At this point crystallization started. -The concentrate was cooled in an ice bath and while stirring 500 milliliters of water was added. After stirring for a period of one hour, the crystalline product was isolated by filtration,

the crystals were washed with water and air-dried to give 688 grams (98.9 percent yield) of 60t-1T16thYl-90L- bromo-l1,8,17a,21-trihydroxy-4-pregnene-3,20-dione 2lacetate (60L-I11thyl-QOC-bI'OmQhYdTOCOItiSOHE 21-acetate) of melting point 159 to 161 degrees centigrade (with de- 2.8 grams of sodium sulfite in 140' 6a-methyl-9BJ 1 ,B-oxido-l 7a,21 -dihydroxy-4- pregnene- 3,20-di0ne 21-acetate To a solution of 6.78 grams of 6oc-I116Ll1Yl-9oL-bIOII10- 11B,17e,21-trihydroxy-4-pregnene-3,20-dione 21-acetate in 175 milliliters of acetone was added 6.78 grams of potassium acetate and the resulting suspension was heated under reflux for a period of seventeen hours. The. mixture was then concentrated to approximately sixty milliliters of volume at reduced pressure on the steamy bath and thereupon diluted with water and extracted with methylene chloride. The methylene extracts were combined, washed with water, dried over anhydrous sodium sulfate and evaporated. The residue was redissolved in methylene chloride and chromatographed over 200 grams of Florisil anhydrous magnesium silicate. The column was eluted with 1050 milliliters of five percent acetone-% Skellysolve B hexanes, 1750 milliliters of eight percent acetone 92% Skellysolve B, 3500 milliliters of ten percent acetone- 90% Skellysolve B and 350 milliliters of acetone. The eluant was collected in 350-rnilliliter fractions. Fractions 616 contained 4.981 grams (88.1% yield) of totally crystalline material. This material was used without further purification in the next step: An analytical sample of 6a-methyl-9/3,1 l 3-oxido-17:1,2l-dihydroxy-4-pregnene- 3,20-dione Zl-acetate, obtained by recrystallization of a portion of the peak fraction from acetone-Skellysolve B hexanes, had a melting point of 180 to 182 degrees 'ce'ntigrade and rotation fal of plus 65 degrees in chloroform.

Analysis.-Calcd. for C H O C, 69.20; H, 7.75. Found: C, 69.41; H, 7.93.

EXAMPLE 13 6a methyl 9oz fluoro 11 9.17.12] trihydroxy 4 pregnene-3,Z0-dior te 21 -acetate (6a-methyl-9a-flu0r0- hydrocortisone ZI-acetate) 7 red colored solution was then kept at approx1mately minus thirty degrees centigrade for one hour and at minus ten degrees for two hours. At the end of this period it was mixed cautiously with an excess of cold sodium bicarbonate solution and the organic material extracted 'with the aid of additional methylene chloride. The combined extracts were Washed with water, dried over anhydrous sodium sulfate and concentrated to approximately '35 milliliters of volume. This solution was chromatogramed over forty milliliters of. Plorisil anhydrous magnesium silicate. The column was diluted with 400 milliliters of seven percent acetone-93% Skellysolve B hexanes, 500 milliliters of ten percent acetone-90% Skellysolve B, 1000 milliliters of twelve percent acetone-88% Skellysolve B hexanes and milliliters of acetone. The eluant was collected in 100 milliliter fractions. Fractions 11 through 17 were combined and evaporated to give a total of 439 milligrams (84.2%) ofcrystalline product. Recrystallization from acetone-Skellysolve B gave two crops: 0.23 gram of melting point 218 to 220, degrees centigrade and 0.16 gram of melting point 201' to 208 degrees centigrade. Total yield 74.7%. An'analytical sample was obtained from ethyl acetate skellysolve B 15 hexanes as needles of pure 6ot-rnethyl-9a-fiuorohydrocortisone 21-acetate of melting point 219 to 220 degrees Centigrade and rotation [0.] plus 113 degrees in acetone. Analysis.-Calcd. for C H O F: C, 66.03; H, 7.62; F, 4.35. Found: C, 65.69; H, 7.49; F, 4.29.

EXAMPLE 13A 6ot-inethyl-9a-fluoro-l 1,8,1 7et,21 -trihydrxy-4-pregn ene- 3,20-di0ne ZI-acetate (alternate procedure) A solution was prepared of 250 milligrams of 6amethyl 95,116 oxido 170:,21 dihydroxy 4 pregnene-3,20-dione 2l-acetate in five milliliters of methylene chloride and thereto was added one milliliter of 48 percent solution of hydrogen fluoride. The two-phase mixture was stirred for a period of twenty hours, then diluted withfifteen milliliters of methylene chloride and carefully poured into forty milliliters of water containing 3.5 grams of sodium bicarbonate. After shaking to neutralize the excess hydrogen fluoride, the methylene chloride was separated and the water phase was extracted with more methylene chloride. The combined methylene chloride solution (about 75 milliliters) was dried over anhydrous sodium sulfate, diluted with 25 milliliters of ether and chromatographed over twenty grams of Florisil synthetic magnesium silicate. The column was eluted as follows:

TABLE II Fraction N o. Solvent 1 (100 milliliters) Methylene chloride-ether (3:1).

2-6 (40 milliliters each) Skellysolve B, hexane plus acetone 7-16 (40 milliliters each) sl fig golve B, hexane plus acetone 17-21(41) milliliters each) slrel l izsolve B, hexane plus acetone 22-26 (40 milliliters each) sl iiz lve B, hexane plus acetone 27-30 (40 milliliters each); slngggsnlve B, hexane plus acetone Fractions 3 to 13, inclusive, were combined, evaporated and the residue thus obtained recrystallized from ethyl acetate-Skellysolve B hexane and from methylene chloride to give 95 milligrams of 6a-methyl-9a-fiuoro-11,3,17a,21- trihydroxy-4-pregnene-3 ,20-dione 21-acetate;

, EXAMPLE 14 6oz methyl 9o: fluoro 17a,21 dihydroxy 4 pregnene-3,11,20-trione ZI-acetate A solution was prepared containing in one milliliter of acetic acid fifty milligrams of. 6a-m-ethyl-9a-fluoro- 11,8,17a,21-trihydroxy-4-pregnene-3,20-dione 21-acetate, twenty milligrams of chromic anhydride and one drop (approximately fifty milligrams) of water. This mixture was shaken'several times at room temperature and allowed to stand for four hours. Thereafter it was poured Three and one quarter (3.25) grams of 6tx-methyl-9lxfluoro llfl,l7a,21 trihydroxy 4 pregnene 3,20

'dione 21-acetate were dissolved in 325 milliliters of methanol, previously purged of air-oxygen 'by passing nitrogen through it for ten minutes and thereto was added a solution of 1.63 grams of potassium bicarbonate in thirty milliliters of Water, similarly purged of oxygen. The mixture was allowed to stand at room temperature for a period of five hours in a nitrogen atmosphere, there upon neutralized with 2.14 milliliters of acetic acid in forty milliliters of water. The mixture was concentrated to approximately one third volume at reduced pressure on a sixty-degree-centigrade water-bath. Thereupon 250 milliliters of water was added and the mixture chilled. The crystalline product was collected on a filter, washed with water and dried to give 2.43 grams (83%) of crude 6a-methyl-9a-fluorohydrocortisone. Recrystallization of the crude material from methanol and Skellysolve B gave pure 6e-methyl-9a-fluorohydrocortisone (6tX-l'l'i6tl1Yl-90tfluoro 11B,17a,21 trihydroxy 4 pregnene- 3,20 dione) of melting point 228 to 230 degrees centigrade and rotation [od plus 112 degrees in acetone.

Analysis.Calcd. for C H O F: C, 66.98; H, 7.92; F, 4.82. Found: C, 67.20; H, 8.01; F, 5.47.

An additional amount of product (0.24 gram, 8.2%) of 6-methyl-9a-fiuorohydrocortisone was obtained by saturating the'filtrate with sodium chloride, extracting with methylene chloride, drying the extracts over'sodium sulfate, evaporating and recrystallizing the thus-obtained residue from benzene-methanol.

'ExAMPLE 16 6 u-methyl-9a-fluoro-l 1 B,] 7 0:,2] -trihydr0xy-4-pregnene- 3,20-dime 21 -m ethanesulfonate 1 To a solution of 2.13 grams of 6a-methyl-9a-fluoro- 1118,1.7ot,21-trihydroxy-4-pregnene-3,ZO-dione in twenty milliliters of pyridine, cooled to zero degrees centigrade, was added one milliliter of methanesulfonyl chloride. The reaction mixture was stirred at five degrees centigrade for a period of seventeen hours, thereafter poured into a mixture of ice and 200 milliliters of aqueous one Normal hydrochloric acid solution. The resulting methanesulfonate was filtered, washed with water, pressed 'dry on a porous plate and then further dried at seventy EXAMPLE 17 One hundred and fifty (150) milligrams of crude 6amethyl 9a fluoro 11/8,l7u,2l trihydroxy 4 pregnene-3,20-dione 21-methanesulfonate was dissolved in fifteen milliliters of acetone and treated with a solution of 0.5 gram of sodium iodide in five milliliters of acetone. The mixture was heated under reflux with stirring for a period of fifteen minutes, the heat then reduced and the mixture concentrated to one third volume at reduced pressure. Ice and water were added and the precipitated product collected on filter, washed with water, and dried over anhydrous sodium sulfate to yield crude 6a-meth ylc fluoro 11,13,170: dihydroxy-21-iodo-4-pregnene-3,20- dione. 5

A solution of 0.1 gram of 60t-mCthy1-9tX-fll10lO-l1,8,170tdihydroxy-Zl-iodo-4-pregnene-3,ZO-dione in fifteen milliliters of acetonitrile was prepared by heating to the boiling point. After cooling to forty degrees centigrade the solution was protected from light, and 0.1 milliliter another hour of stirring, an additional 0.1 milliliter portion of silver fluoride solution was added and heating and stirring continued for a period of two hours. The brownish mixture was thereupon filtered through a bed of Celite diatomaceous earth and the filtrate was evap orated at reduced pressure from a bath at a temperature of fifty degrees centigrade. The brown residue was thoroughly extracted with three ten-milliliter portions of warm methylene chloride, the extracts combined, washed with water, dried over anhydrous sodium sulfate and concentrated to approximately eight milliliter volume. The material was then filtered again, evaporated and three times recrystallized from methanol and water to yield 6a-methyl-9a,21difluoro-1 1B,17u-dihydroxy-4-pregnone-3,20-dione of melting point 210 to 212 degrees centigrade with decomposition.

EXAMPLE 19 6a methyl 90:,21 difluoro 115,17 dihydroxy 4- pregnene-3,20-dione from 6u-methyl-9ot-flu0r0-I15,17, 21-trihydr0xy-4-pregnene-3,20-dione 21 -meth anesulfonate A solution of 1.10 grams of 6a-methyl-9a-fluoro-11p, 17,2l-trihydroxy-4-pregnene-3,ZO-dione 21-methanesulfonate in ten milliliters of dimethylsulfoxide was prepared by heating to approximately 100 degrees centigrade. Thereto was added 550 milligrams of potassium fluoride and the resulting suspension was stirred and heated at a temperature between 100 and 110 degrees centigrade for a period of eighteen hours. The mixture was then cooled, 200 milliliters of water were added and the water phase extracted with methylene chloride and the extracts washed with water, dried over anhydrous sodium sulfate and concentrated to about forty milliliters of volume. This solution was chromatographed over fifty grams of Florisil anhydrous magnesium silicate taking fractions of one hundred milliliters as follows:

TABLE III Fraction No. Solvent Skellysolve B hexanes-acetone 90:10. Skellysolve B hexanes-acetone 88:12.

acetone.

EXAMPLE 20 Three 100-milliliter portions of a medium, in 250- milliliter Erlenmeyer flasks, containing one percent glucose, two percent corn steep liquor (sixty percent solids) and tap water, were adjusted to a pH of 4.9. This medium was sterilized for 45 minutes at fifteen pounds per square inch pressure and inoculated with a one to two day growth of Septorrzyxa ajfinis A. T. C. C. 6737. The Erlenmeyer flask was shaken at room temperature (about 26 to 28 degrees centigrade) for a period of three days. At the end of this period this BOO-milliliter volume was used as an inoeulum for five liters of the same 15 milliliter portions of acetone.

18 glucose-corn steep liquor medium which in addition contained five milliliters of an antifoam compound (a mixture of lard oil and octadecanol). The fermentor was placed into the water bath, adjusted to 28 degrees centigrade and the contents stirred (300 R. P. M.) and aerated (0.3 liter air to five liters of beer). After twenty hours of incubation, when a good growth had been developed, one gram of 6m-methyl-9a-2l-difluoro-l113,17a-dihydroxy- 4-pregnene-3,20-dione plus one-half gram of 3-ketobisnor- 4-cholen-22-al, dissolved in sixteen milliliters of dimethylformamide, was added and the incubation carried out at the same temperature (28 degrees centigrade) and aeration for a period of 72 hours (final pH 8.3). The mycelium was filtered off and extracted with three 200- The beer was extracted with three one-liter portions of methylene chloride and thereupon the extracts of the beer and acetone were combined, dried over anhydrous sodium sulfate, evaporated and the resulting residue chromatographed over a Florisil anhydrous magnesium silicate column. The

column was packed with 100 grams of Florisil and was developed with five 200-milliliter fractions each of methylene chloride, Skellysolve B hexane-acetone mixtures of 9:1, 8:2, 7:3, 1:1, and methanol. The fraction eluted with Skellysolve B acetone (8:2) was twice re crystallized from acetone to give 6a-methyl-9a,21-difluoro-11B,17a-dihydroxy-1,4-pregnadiene-3-20-dione of melting point 262 to 274 degrees centigrade and rotation [al plus 71 degrees in acetone.

30 In a manner similar to Example 20 using other species of genus Septomyxa under fermentation conditions known in the art, preferably in the presence of a promoting agent such as 3-ketobisnor-4-eholen-22-al, progesterone, 115,21 dihydroxy 1,4,l7(20) pregnatrien 3 one,

3-ketobisnor-4-cholenic acid and the like, produces from 6 methyl 9a,21-difluoro-11p,17a-dihydroxy-4-pregnene- 3,20 dione the 6 methyl 9u,2l-difluoro 115,170 dihydroxy-1,4-pregnadiene-3,ZO-dione. Instead of a species of the genus Septomyxa, species of other genera such as Corynebacterium, Didymella, Calonectria, Alternaria, Colletotrichum, Cylindrocarpon, Ophiobolus, Fusarium, Listeria, Erysipelothrix, Mycobacterium, Tricothecium, Leptosphaeria, Cucurbitaria, Nocardia, and enzymes of fungi of the family Tuberculariaceae can be used to introduce a A -bond into 6-methyl-9a-21-difluoro-115,17u-

dihydroxy-4-pregnene-3,20-dione.

It is to be understood that the invention is not to be limited to the exact details of operation or exact compounds shown and described, as obvious modifications and equivalents will be apparent to one skilled in the art and the invention is therefore to be limited only by the scope of the appended claims.

We claim:

1. A compound selected from the group consisting of 6 methyl 90.,21 difluoro 11am dihydroxy 4 pregnene-3-20-dione and 6-methyl-9a,21-difluoro-17a-hydroxy-4-pregnene-3,l 1,20-trione.

2. 6oz methyl 9a,21 difluoro 113,17 dihydroxy 4-pregnene-3,20-dione.

3. 6oz methyl 9a,21 difluoro 17 hydroxy 4 pregame-3,1 1,20-trione.

4. 6a methyl 9a fluoro 115,171: dihydroxy 21 iodo-4-pregnene-3,20-dione.

References Cited in the file of this patent Herz et al.: J. A. C. S. 78, September 20, 1956, pages 4812-4814.

Spero et al.: I. A. C. S. 78, December 5, 1956, pages 0 6213, 6214.

UNITED STATES PATENT OFFICE Certificate of Correction Patent No. 2,867,635

Frank H. Lincoln, Jr. et al.

January 6, 1959 It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction and that the said Letters as corrected below.

as in the patent- Patent should read Column 2, lines 15 to 25, Formula IX should appear as shown below instead oi H: column 7, line 25, for unually read -usually-. Signed and sealed this l lth day of July 1959.

Attest KARL H. mm--- ROBERT C. WATSON, Attracting Oficer.

Commissioner of Patents. 

1. A COMPOUND SELECTED FROM THE GROUP CONSISTING OF 6 - METHYL - 9A,21 - DIFLUORO - 11B,17A - DIHYDROXY - 4 PREGNENE-3-20-DIONE AND 6-METHYL-9A,21-DIFLUORO-17A-HYDROXY-4-PREGNENE-3,11,20-TRIONE. 